The Play Tween action allows you to start going through the frames in a tween from the start.
When you create a Tween object you can set the Play Automatically option to automatically start the animation at the frame rate set on the Properties page for that tween. If you do not want this to happen you can deselect this option and use the Play Tween action to start the tween playing at some other moment in your publication.
Note:
Whilst waiting for the Play Tween action an inactive Tween will still be visible with the first frame showing, unless you set it to be hidden. In which case you will need a Show action prior to the Play Tween.
Add the Play Tween action to your trigger, as described in adding actions. The Tween list will automatically appear when you add the action.
Click on the name of the Tween object in the Tween object list that you want to use with this action.
Click on the Apply button to save your changes.